Regulation, institutions, and commitment : privatization and regulation in the Argentine telecommunications sector

In 1990, Argentina privatized its state-owned telephone company, ENTel. Shifting telecommunications to the private sector was one of the first actions taken under the reform program of the new president, Carlos Saul Menem. In privatizing ENTel, the government focused on privatization as a way of establishing its reform credentials. Establishing a post-privatization regulatory regime was given lower priority. A well-defined regulatory regime was not in place before the sale, but privatization took place nonetheless. The authors find that despite the delay in implementing a regulatory regime, ENTel's privatization appears to have had a net positive impact, both on Argentina's reputation and on welfare. The reform program had its own virtuous cycle, creating and reinforcing credibility in the short run. But the neglect of the regulatory regime appears to have been costly in terms of the sale price that the government received and the tariff levels that investors demanded. In the long run, this neglect, if it persists, may have a negative impact on the telecommunications sector's performance. Regulation plays an important role in the private provision of telecommunications. Many argue that competition should be limited to allow economies of scale. But limited competition can lead to abuses of monopoly power and to demands from customers and suppliers for a regulatory regime to protect them from such abuses. In addition, the sector requires high sunk costs and asset specificity and the assets'owners are particularly exposed to the risks of expropriation - either outright (through nationalization) or gradual (through service requirements or low tariffs). A stable, credible regulatory environment reduces the risk of investment in this sector and reduces the expected rate of return that private investors would require to participate. Establishing a stable, credible regulatory regime before privatization increases the value of a privatized telecommunications firm to potential purchasers by reducing the risk associated with the purchase. This in turn affects the price generated by the selling government. By failing to establish such a regime in advance, the Argentine government received a lower sale price and increased the probability that buyers would capture windfall profits.ICT Policy and Strategies,Public Sector Economics&Finance,Environmental Economics&Policies,Parliamentary Government,National Governance

Growing Appalachia: Local Foods & Community Development in Knox County, Kentucky

This poster highlights the work of the Lend-A-Hand Center Grow Appalachia Gardening Program, the Knox County Farmers’ Market, and the “Local Foods, Local Places” grant program. The Lend-A-Hand Center is a nondenominational community service organization in Walker, Kentucky, that was started in 1958 by Irma Gall and Peggy Kemner (ASA Helen M. Lewis Community Service Award Recipients). Grow Appalachia is a program begun in 2009 administered by Berea College to promote gardening and local food systems in Appalachia. The Lend-A-Hand Center Grow Appalachia Project was begun in 2014 to break down barriers to gardening and build community, addressing food security issues in Knox County through providing resources and technical assistance for home and community gardens. The Knox County Farmers’ Market was also begun in 2014 and was successfully established as an important community institution in Barbourville. Also in 2014 Barbourville was one of 26 communities nationwide selected to participate in the federally funded “Local Foods, Local Places” program. This poster details the development and success of these programs and looks to future local foods initiatives in the area

Evaluation of the Performance Characteristics of the CGLSS and NLDN Systems Based on Two Years of Ground-Truth Data from Launch Complex 39B, Kennedy Space Center, Florida

From May 2011 through July 2013, the lightning instrumentation at Launch Complex 39B (LC39B) at the Kennedy Space Center, Florida, has obtained high-speed video records and field change waveforms (dE/dt and three-axis dH/dt) for 54 negative polarity return strokes whose strike termination locations and times are known with accuracy of the order of 10 m or less and 1 s, respectively. A total of 18 strokes terminated directly to the LC39B lighting protection system (LPS), which contains three 181 m towers in a triangular configuration, an overhead catenary wire system on insulating masts, and nine down conductors. An additional 9 strokes terminated on the 106 m lightning protection mast of Launch Complex 39A (LC39A), which is located about 2.7 km southeast of LC39B. The remaining 27 return strokes struck either on the ground or attached to low-elevation grounded objects within about 500 m of the LC39B LPS. Leader/return stroke sequences were imaged at 3200 frames/sec by a network of six Phantom V310 high-speed video cameras. Each of the three towers on LC39B had two high-speed cameras installed at the 147 m level with overlapping fields of view of the center of the pad. The locations of the strike points of 54 return strokes have been compared to time-correlated reports of the Cloud-to-Ground Lightning Surveillance System (CGLSS) and the National Lightning Detection Network (NLDN), and the results of this comparison will be presented and discussed

Diffraction gratings of isotropic negative phase-velocity materials

Diffraction of electromagnetic plane waves by the gratings made by periodically corrugating the exposed planar boundaries of homogeneous, isotropic, linear dielectric--magnetic half--spaces is examined. The phase velocity vector in the diffracting material can be either co-parallel or anti-parallel to the time-averaged Poynting vector, thereby allowing for the material to be classified as of either the positive or the negative negative phase-velocity (PPV or NPV) type. Three methods used for analyzing dielectric gratings - the Rayleigh-hypothesis method, a perturbative approach, and the C formalism - are extended here to encompass NPV gratings by a careful consideration of field representation inside the refracting half--space. Corrugations of both symmetric as well as asymmetric shapes are studied, as also the diversity of grating response to the linear polarization states of the incident plane wave. The replacement of PPV grating by its NPV analog affects only nonspecular diffraction efficiencies when the corrugations are shallow, and the effect on specular diffraction efficiencies intensifies as the corrugations deepen. Whether the type of the refracting material is NPV or PPV is shown to affect surface wave propagation as well as resonant excitation of surface waves.Comment: 28 pages, 10 figures in 27 file

The general anaesthetic etomidate inhibits the excitability of mouse thalamocortical relay neurons by modulating multiple modes of GABA_A receptor-mediated inhibition

Modulation of thalamocortical (TC) relay neuron function has been implicated in the sedative and hypnotic effects of general anaesthetics. Inhibition of TC neurons is mediated predominantly by a combination of phasic and tonic inhibition, together with a recently described ‘spillover’ mode of inhibition, generated by the dynamic recruitment of extrasynaptic γ-aminobutyric acid (GABA)(A) receptors (GABA(A)Rs). Previous studies demonstrated that the intravenous anaesthetic etomidate enhances tonic and phasic inhibition in TC relay neurons, but it is not known how etomidate may influence spillover inhibition. Moreover, it is unclear how etomidate influences the excitability of TC neurons. Thus, to investigate the relative contribution of synaptic (α1β2γ2) and extrasynaptic (α4β2δ) GABA(A)Rs to the thalamic effects of etomidate, we performed whole-cell recordings from mouse TC neurons lacking synaptic (α1(0/0)) or extrasynaptic (δ(0/0)) GABA(A)Rs. Etomidate (3 μm) significantly inhibited action-potential discharge in a manner that was dependent on facilitation of both synaptic and extrasynaptic GABA(A)Rs, although enhanced tonic inhibition was dominant in this respect. Additionally, phasic inhibition evoked by stimulation of the nucleus reticularis exhibited a spillover component mediated by δ-GABA(A)Rs, which was significantly prolonged in the presence of etomidate. Thus, etomidate greatly enhanced the transient suppression of TC spike trains by evoked inhibitory postsynaptic potentials. Collectively, these results suggest that the deactivation of thalamus observed during etomidate-induced anaesthesia involves potentiation of tonic and phasic inhibition, and implicate amplification of spillover inhibition as a novel mechanism to regulate the gating of sensory information through the thalamus during anaesthetic states

Downregulation of aquaporin 3 inhibits cellular proliferation, migration and invasion in the MDA‑MB‑231 breast cancer cell line

Aquaporins are membrane proteins that regulate cellular water flow. Recently, aquaporins have been proposed as mediators of cancer cell biology. A subset of aquaporins, referred to as aquaglyceroporins are known to facilitate the transport of glycerol. The present study describes the effect of gene knockdown of the aquaglyceroporin AQP3 on MDA‑MB‑231 breast cancer cell proliferation, migration, invasion, adherence and response to the chemotherapeutic agent 5‑fluorouracil. shRNA mediated AQP3 gene knockdown induced a 28% reduction in cellular proliferation (P<0.01), a 39% decrease in migration (P<0.0001), a 24% reduction in invasion (P<0.05) and a 25% increase in cell death at 100 µM 5‑FU (P<0.01). Analysis of cell permeability to water and glycerol revealed that MDA‑MB‑231 cells with knocked down AQP3 demonstrated a modest decrease in water permeability (17%; P<0.05) but a more marked decrease in glycerol permeability (77%; P<0.001). These results suggest that AQP3 has a role in multiple aspects of breast cancer cell pathophysiology and therefore represents a novel target for therapeutic intervention

The Wikipedia Gender Gap Revisited: Characterizing Survey Response Bias with Propensity Score Estimation

Opt-in surveys are the most widespread method used to study participation in online communities, but produce biased results in the absence of adjustments for non-response. A 2008 survey conducted by the Wikimedia Foundation and United Nations University at Maastricht is the source of a frequently cited statistic that less than 13% of Wikipedia contributors are female. However, the same study suggested that only 39.9% of Wikipedia readers in the US were female – a finding contradicted by a representative survey of American adults by the Pew Research Center conducted less than two months later. Combining these two datasets through an application and extension of a propensity score estimation technique used to model survey non-response bias, we construct revised estimates, contingent on explicit assumptions, for several of the Wikimedia Foundation and United Nations University at Maastricht claims about Wikipedia editors. We estimate that the proportion of female US adult editors was 27.5% higher than the original study reported (22.7%, versus 17.8%), and that the total proportion of female editors was 26.8% higher (16.1%, versus 12.7%).Sloan School of ManagementHarvard University. Berkman Center for Internet & SocietyFord Visionary Leadership FundNorthwestern University (Evanston, Ill.

Mortality, fertility, and the OY ratio in a model hunter–gatherer system

An agent‐based model (ABM) is used to explore how the ratio of old to young adults (the OY ratio) in a sample of dead individuals is related to aspects of mortality, fertility, and longevity experienced by the living population from which the sample was drawn. The ABM features representations of rules, behaviors, and constraints that affect person‐ and household‐level decisions about marriage, reproduction, and infant mortality in hunter–gatherer systems. The demographic characteristics of the larger model system emerge through human‐level interactions playing out in the context of “global” parameters that can be adjusted to produce a range of mortality and fertility conditions. Model data show a relationship between the OY ratios of living populations (the living OY ratio) and assemblages of dead individuals drawn from those populations (the dead OY ratio) that is consistent with that from empirically known ethnographic hunter–gatherer cases. The dead OY ratio is clearly related to the mean ages, mean adult mortality rates, and mean total fertility rates experienced by living populations in the model. Sample size exerts a strong effect on the accuracy with which the calculated dead OY ratio reflects the actual dead OY ratio of the complete assemblage. These results demonstrate that the dead OY ratio is a potentially useful metric for paleodemographic analysis of changes in mortality and mean age, and suggest that, in general, hunter–gatherer populations with higher mortality, higher fertility, and lower mean ages are characterized by lower dead OY ratios. Am J Phys Anthropol 154:222–231, 2014. © 2014 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106895/1/ajpa22495.pd

Metadata behind the Interoperability of Wireless Sensor Networks

Wireless Sensor Networks (WSNs) produce changes of status that are frequent, dynamic and unpredictable, and cannot be represented using a linear cause-effect approach. Consequently, a new approach is needed to handle these changes in order to support dynamic interoperability. Our approach is to introduce the notion of context as an explicit representation of changes of a WSN status inferred from metadata elements, which in turn, leads towards a decision-making process about how to maintain dynamic interoperability. This paper describes the developed context model to represent and reason over different WSN status based on four types of contexts, which have been identified as sensing, node, network and organisational contexts. The reasoning has been addressed by developing contextualising and bridges rules. As a result, we were able to demonstrate how contextualising rules have been used to reason on changes of WSN status as a first step towards maintaining dynamic interoperability